Method of additively manufacturing a heat exchanger component with embedded sensor

ABSTRACT

An additively manufactured component is provided. The additively manufactured component includes an additively manufactured first part defining a first trench, an additively manufactured second part defining a second trench and a fiber optic sensor. The additively manufactured first and second parts are additively manufactured together with the first and second trenches corresponding in position such that the additively manufactured first and second parts form an assembled part with a fiber channel cooperatively defined by the first and second trenches. The fiber optic sensor includes a first sensor part embedded in the fiber channel and a second sensor part operably coupled to the first sensor part and extendible at an exterior of the assembled part.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No.15/381,809, filed Dec. 16, 2016. The entire contents of U.S. applicationSer. No. 15/381,809 are incorporated herein by reference.

BACKGROUND

The following description relates to heat exchangers and, moreparticularly, to heat exchanger components with embedded sensors thatare assembled by way of additive manufacturing such as direct metallaser sintering (DMLS) or other three-dimensional (3D) printing methods.

Monitoring performance or conditions inside certain devices can bechallenging. For example, determining temperatures inside gas turbineengines often require that special temperature sensors, which cansurvive in very high temperature and high pressure environments be usedbut those types of features can be expensive and often require thatadditional structural supports be built inside the devices. Moreover,the specialized sensors and their associated structures can have poorreliability characteristics.

BRIEF DESCRIPTION

According to one aspect of the disclosure, an additively manufacturedcomponent is provided. The additively manufactured component includes anadditively manufactured first part defining a first trench, anadditively manufactured second part defining a second trench and a fiberoptic sensor. The additively manufactured first and second parts areadditively manufactured together with the first and second trenchescorresponding in position such that the additively manufactured firstand second parts form an assembled part with a fiber channelcooperatively defined by the first and second trenches. The fiber opticsensor includes a first sensor part embedded in the fiber channel and asecond sensor part operably coupled to the first sensor part andextendible at an exterior of the assembled part.

In accordance with additional or alternative embodiments, the additivelymanufactured first and second parts are formed from at least one offused deposition modeling (FDM), fused filament fabrication (FFF),direct ink writing (DIW), stereo-lithography (SLA), digital lightprocessing (DLP), powder bed and inkjet 3D printing (3DP), powder bedfusion (PBF), electron beam melting (EBM), selective laser melting(SLM), selective heat sintering (SHS), selective laser sintering (SLS),direct metal laser sintering (DMLS), laminated object manufacturing(LOM), directed energy deposition and electron beam freeform fabrication(EBF³).

In accordance with additional or alternative embodiments, at least oneof the additively manufactured first and second parts includes at leastone of aluminum (Al), nickel (Ni), titanium (Ti), cobalt-based alloys,steels, ceramics, cermets, photopolymers and thermoplastics.

In accordance with additional or alternative embodiments, a central axisof the fiber channel is offset from respective planes of outermostlayers of the additively manufactured first and second parts.

In accordance with additional or alternative embodiments, the fiberoptic sensor is at least one of a strain sensor and a temperature sensorand further includes a processing unit to process sensor readingsobtained by the first part.

In accordance with additional or alternative embodiments, each of theadditively manufactured first and second parts defines multiple firstand second trenches, respectively, such that the assembled part hasmultiple fiber channels and the fiber optic sensor includes multiplefirst sensor parts respectively embedded in a corresponding one of themultiple fiber channels.

In accordance with additional or alternative embodiments, the firstsensor part includes a thermal barrier coating (TBC).

In accordance with additional or alternative embodiments, the firstsensor part and the TBC tightly fit in the fiber channel.

In accordance with additional or alternative embodiments, the firstsensor part and the TBC are embedded with pre-loading in the fiberchannel.

In accordance with additional or alternative embodiments, the TBCincludes a protruding surface feature and the fiber channel is definedby a corresponding one of the first and second trenches to include arecessed surface feature corresponding in position to the protrudingsurface feature.

In accordance with additional or alternative embodiments, the fiberchannel is defined by the first and second trenches to include first andsecond transverse channel components in which corresponding sections ofthe first sensor part and the TBC are respectively embedded.

In accordance with another aspect of the disclosure, a fiber opticsensor is provided for operable disposition in a fiber channel of anadditively manufactured component. The fiber optic sensor includes afirst sensor part embedded in the fiber channel and comprising anexterior surface and a thermal barrier coating (TBC) disposed thereon toprotect the exterior surface during additive manufacturing processes, asecond sensor part operably coupled at a first end thereof to the firstsensor part and extendible at an exterior of the assembled part and aprocessing unit operably coupled to a second end of the second sensorpart to process sensor readings obtained by the first part.

In accordance with additional or alternative embodiments, the firstsensor part is configured for at least one of strain and temperaturesensing.

In accordance with additional or alternative embodiments, the TBCincludes a protruding surface feature that corresponds with a recessedsurface feature of the fiber channel.

In accordance with additional or alternative embodiments, the firstsensor part and the TBC each have corresponding sections that arerespectively embedded in first and second transverse components of thefiber channel.

According to yet another aspect of the disclosure, a method ofadditively manufacturing a component is provided. The method includesadditively manufacturing a first part to define a trench, laying down anoptical fiber in the trench and additively manufacturing a second partonto the first surface and around the optical fiber to extend the trenchinto a fiber channel in which the optical fiber is embedded.

In accordance with additional or alternative embodiments, the additivemanufacturing of the first and second parts includes at least one offused deposition modeling (FDM), fused filament fabrication (FFF),direct ink writing (DIW), stereo-lithography (SLA), digital lightprocessing (DLP), powder bed and inkjet 3D printing (3DP), powder bedfusion (PBF), electron beam melting (EBM), selective laser melting(SLM), selective heat sintering (SHS), selective laser sintering (SLS),direct metal laser sintering (DMLS), laminated object manufacturing(LOM), directed energy deposition and electron beam freeform fabrication(EBF³).

In accordance with additional or alternative embodiments, the methodfurther includes pre-loading optical fiber and the TBC in the fiberchannel.

In accordance with additional or alternative embodiments, the applyingof the TBC includes forming a protruding surface feature and theadditive manufacturing of the second part around the optical fiberincludes forming a recessed surface feature corresponding in position tothe protruding surface feature.

In accordance with additional or alternative embodiments, the additivemanufacturing of the first part includes forming the trench to includefirst and second transverse components, the laying down of the opticalfiber includes laying down sections of the optical fiber with the TBCapplied thereto in the first and second transverse components and theadditively manufacturing of the second part includes extending the firstand second transverse components of the trench into first and secondtransverse components of the fiber channel.

These and other advantages and features will become more apparent fromthe following description taken in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter, which is regarded as the disclosure, is particularlypointed out and distinctly claimed in the claims at the conclusion ofthe specification. The foregoing and other features, and advantages ofthe disclosure are apparent from the following detailed descriptiontaken in conjunction with the accompanying drawings in which:

FIG. 1 is a perspective view of an assembled part with an embedded fiberoptic sensor in accordance with embodiments;

FIG. 2 is a side schematic view of the assembled part of FIG. 1;

FIG. 3 is an enlarged schematic view of components of an additivelymanufactured first part of the assembled part of FIG. 1;

FIG. 4 is an enlarged schematic view of components of an additivelymanufactured second part of the assembled part of FIG. 1;

FIG. 5 is a diagram illustrating an additive manufacturing process foradditively manufacturing a first part of the assembled part of FIG. 1;

FIG. 6 is a diagram illustrating an additive manufacturing process foradditively manufacturing a second part of the assembled part of FIG. 1;

FIG. 7 is an enlarged schematic illustration of a fiber optic sensorpositioned between additively manufactured first and second parts inaccordance with embodiments;

FIG. 8 is an enlarged schematic illustration of preloading of a fiberoptic sensor in accordance with embodiments;

FIG. 9 is a top down view of protruding and recessed features to securea fiber optic sensor within a fiber channel in accordance withembodiments; and

FIG. 10 is a top down view of a complex pathway of a fiber optic sensorwithin an assembled part in accordance with embodiments.

DETAILED DESCRIPTION

As will be described below, additive manufacturing techniques areapplied to allow for the integration of sensing elements into astructure or assembled part so that a self-aware component can berealized. Such components can monitor performance or conditions insideand outside of the self-aware component without the need to add onaddition components that reduce reliability and increase cost. In anexemplary case, an additive build process is executed to provide acomponent with a shallow trench of about 75 microns in diameter in whichan optical fiber can be placed. The additive build process proceeds andencases the optical fiber inside the resulting component. Optical leadsare routed from the optical fiber to a transducer where sensor readingsare converted to electrical signals as required for processing.

In some cases, a thin thermal coating can be provided on the opticalfiber so that the optical fiber (melting point ˜1700° C.) can withstandat least a few microseconds at a melt pool maximum temperature (˜2900°C.) associated with certain additive manufacturing processes. Internalhealth monitoring can be performed to determine component temperaturesor structural integrity issues for select locations with multipleleads/wires to thereby ensure robustness and to preclude reliabilitylimitations.

With reference to FIGS. 1-4, an additively manufactured component 10 isprovided. The additively manufactured component 10 includes anadditively manufactured first part 11, an additively manufactured secondpart 12 and a fiber optic sensor 13. The additively manufactured firstpart 11 includes a body 110 that is formed of multiple layers 111 andthe additively manufactured second part 12 includes a body 120 that isformed of multiple layers 121. For the non-limiting and exemplaryembodiment in which the fiber optic sensor 13 is disposed between anupper surface 112 of the additively manufactured first part 11 and alower surface 122 of the additively manufactured second part 12, themultiple layers 111 proximate to the upper surface 112 cooperativelydefine at least a segment of a first trench 113 with the uppermost oneof the multiple layers 111 actually forming the upper surface 112 (seeFIG. 3) and the multiple layers 121 proximate to the lower surface 122cooperatively define at least a segment of a second trench 123 with thelowermost one of the multiple layers 121 actually forming the lowersurface 122 (see FIG. 4).

The additively manufactured first and second parts 11 and 12 areadditively manufactured together. That is, the lower surface 122 of theadditively manufactured second part 12 is additively manufactured ontothe upper surface 112 of the additively manufactured first part 11 inthe non-limiting and exemplary embodiment provided above. The additivelymanufactured first and second parts 11 and 12 thus form an assembledpart 14. Therefore, with the first and second trenches 113 and 123corresponding with one another in terms of at least their respectivepositions, the first and second trenches 113 and 123 cooperativelydefine an optical fiber channel 15.

The fiber optic sensor 13 may be configured for sensing strain and/ortemperature within the assembled part 14 and includes a first sensorpart 130, a second sensor part 131 and a processing unit 132. The firstsensor part 130 is embedded in the fiber channel 15. The second sensorpart 131 is operably coupled at a first end thereof to the first sensorpart 130 and is extendible at an exterior of the assembled part 14. Theprocessing unit 132 is operably coupled to a second end of the secondsensor part 131 and is configured to process and to analyze sensorreadings obtained by the first sensor part 130. In doing so, theprocessing unit 132 may be configured to consider heat transfercapabilities of the materials of the assembled part 14. That is, if theassembled part 14 is disposed within a high temperature and highpressure fluid flow of, for example, a gas turbine engine, the interiorof the assembled part 14 where the fiber optic sensor 13 is located willbe heated at a different rate as compared to the peripheral portionsthat are closer to the actual fluid flow. In any case, the processingunit 132 can be used to determine both the temperature of the interiorof the assembled part 14 and to calculate temperatures of the peripheralportions of the assembled part 14 from the interior temperature.

With reference to FIGS. 5 and 6, the additively manufactured first andsecond parts 11 and 12 may be fabricated by at least one or more offused deposition modeling (FDM), fused filament fabrication (FFF),direct ink writing (DIW), stereo-lithography (SLA), digital lightprocessing (DLP), powder bed and inkjet 3D printing (3DP), powder bedfusion (PBF), electron beam melting (EBM), selective laser melting(SLM), selective heat sintering (SHS), selective laser sintering (SLS),direct metal laser sintering (DMLS), laminated object manufacturing(LOM), directed energy deposition and electron beam freeform fabrication(EBF³). In accordance with embodiments, the additively manufacturedfirst and second parts 11 and 12 may be formed of at least one or moreof aluminum (Al), nickel (Ni), titanium (Ti), cob alt-based alloys orany other type of metallic alloys, stainless or non-stainless steels,ceramics, cermet, photopolymers, powdered polymers and thermoplastics.

In an exemplary case where the additively manufactured first and secondparts 11 and 12 are formed from DMLS and are made of aluminum (Al), asshown in FIG. 5, the multiple layers 111 are laid down on a jig 20 insequence with each of the multiple layers 111 being formed of metallicpowder that is deposited and then melted and bonded to surroundingmetallic materials by a laser that passes over the surface area of thedeposited metallic powder. As the multiple layers 111 are built up ontop of lower layers and reaches the height of the first trench 113, thelaser avoids passing over the region where the first trench 113 is to beformed. This avoids the creation of metallic bonds and results in thedefinition of the segment of the first trench 113 once all of themultiple layers 111 are finally formed.

As shown in FIG. 6, the multiple layers 121 are similarly laid down onthe upper surface 112 (instead of the jig 20). As such, each of themultiple layers 121 is formed of metallic powder that is deposited andthen melted and bonded to surrounding metallic materials by the laser.As the multiple layers 121 are built up on top of lower layers at theheight of the second trench 123, the laser avoids passing over theregion where the second trench 123 is to be formed so as to avoid thecreation of metallic bonds in this region with the result being thedefinition of at least the segment of the second trench 123 once themultiple layers 121 are finally formed.

With reference to FIG. 7, a central axis of the fiber channel 15 can bealigned with or offset from respective planes of outermost layers (i.e.,the upper surface 112 and the lower surface 122) of the additivelymanufactured first and second parts 11 and 12. In the former case, wherethe fiber channel 15 has a circular cross-sectional shape, for example,the first trench 113 and the second trench 123 would each be formed tohave semi-circular cross-sectional shapes of substantially similar size.In the latter case, where again the fiber channel 15 has the circularcross-sectional shape, the first trench 113 can be formed to have asegmented-circular shape that is larger or smaller than a semi-circleand the second trench 123 can be formed to have a complementarilysegmented-circular shape that is smaller or larger than the semi-circle.

With reference back to FIGS. 1 and 2, each of the additivelymanufactured first and second parts 11 and 12 can be formed to definemultiple first and second trenches 113 and 123, respectively, such thatthe assembled part 14 has multiple fiber channels 15. Similarly, thefiber optic sensor 13 may include or be provided with multiple firstsensor parts 130 that are each respectively embedded in a correspondingone of the multiple fiber channels 15.

With continued reference back to FIG. 2, additive manufacturingprocesses can generate extremely high local temperatures at locationswhere the laser light is incident on the deposited metallic powder.Where the additive manufacturing processing include DMLS and thedeposited metallic powder includes aluminum (which has a meltingtemperature of about 660° C. and a boiling temperature of about 2519°C.) or nickel (which has a melting temperature of about 1455° C. and aboiling temperature of about 2913° C.), for example, the localtemperatures at which DMLS occurs can exceed the temperature range atwhich the fiber optic sensor 13 can be damaged. This is true even forhigh-purity, telecom-grade optical fibers whose melting point is around1700° C. As such, as shown in FIG. 2, at least the first sensor part 130of the optical fiber sensor 13 may include an exterior surface 801 and athermal barrier coating (TBC) 802. The TBC 802 is applied to theexterior surface 801 and thus disposed to protect the exterior surface801 and the first sensor part 130/optical fiber sensor 13 as a wholefrom thermal damage resulting from the DMLS processing.

With continued reference to FIG. 2 and, in accordance with embodiments,the first sensor part 130 and the TBC 802 (if applicable) are disposedto tightly fit in the fiber channel 15. That is, where an interiorsurface of the TBC 802 conforms to a contour of the exterior surface801, an interior surface of the fiber channel 15 conforms to a contourof an exterior surface of the TBC 802. As such, the first sensor part130 can be securely held by frictional contact between abutting surfacesin the fiber channel 15.

With reference to FIG. 8 and, in accordance with further embodiments,the first sensor part 130 and the TBC 802 (if applicable) are embeddedwith pre-loading in the fiber channel 15. This can be accomplished, forexample, by laying down the first sensor part 130 and the TBC 802 in thefirst trench 112 and then applying localized pressure thereto (e.g., bypushing down on the TBC 802 with a probe) while the additivelymanufactured second part 12 is built up around them. Once the locallypressurized sections of the first sensor part 130 and the TBC 802 aresurrounded by material of the additively manufactured second part 12,the application of the localized pressure is relieved (e.g., by removingthe probe) and the additively manufactured second part 12 is completed.The resulting preloading can increase frictional contact betweenabutting surfaces in the fiber channel 15 and can be accounted for bythe processing unit 132 in analyzing sensor readings.

With reference to FIG. 9 and, in accordance with further embodiments, atleast the TBC 802 may include a protruding surface feature 901 and thefiber channel 15 may be defined by a corresponding one of the first andsecond trenches 113 and 123 to include a recessed surface feature 902which corresponds in position to the protruding surface feature 901. Theprotruding surface feature 901 can be a bump or a hook shaped elementand the recessed surface feature 902 can be a dimple that is receptiveof the bump or a reversed hook that engages with the hook shapedelement. In either case, the protruding surface feature 901 and therecessed surface feature 902 mechanically interact with one another tosecure the first sensor part 130 in place within the fiber channel 15.The protruding surface feature 901 can be built up of the TBC 802 aloneor may be formed as part of the first sensor part 130. In the lattercase, the TBC 802 is simply built up around and over the formation ofthe first sensor part 130.

With reference to FIG. 10, the fiber channel 15 may be defined by thefirst and second trenches 113 and 123 (see FIG. 2) to include first andsecond transverse channel components 151 and 152. Within such first andsecond transverse channel components 151 and 152, corresponding sections153 and 154 of the first sensor part 130 and the TBC 802 (if applicable)may be respectively embedded. With this configuration, multiple regionsof the assembled part 14 can be accessible to the first sensor part 130and the torturous path followed by the first sensor part 130 serves tosecure the first sensor part 130 within the fiber channel 15.

While the disclosure is provided in detail in connection with only alimited number of embodiments, it should be readily understood that thedisclosure is not limited to such disclosed embodiments. Rather, thedisclosure can be modified to incorporate any number of variations,alterations, substitutions or equivalent arrangements not heretoforedescribed, but which are commensurate with the spirit and scope of thedisclosure. Additionally, while various embodiments of the disclosurehave been described, it is to be understood that the exemplaryembodiment(s) may include only some of the described exemplary aspects.Accordingly, the disclosure is not to be seen as limited by theforegoing description, but is only limited by the scope of the appendedclaims.

What is claimed is:
 1. A method of additively manufacturing a component,the method comprising: additively manufacturing a first part such that afirst surface thereof defines a trench; laying down an optical fiber inthe trench; additively manufacturing a second part onto the firstsurface and around the optical fiber such that the first part and thesecond part redefine the trench as a fiber channel in which the opticalfiber is embedded; and applying a thermal barrier coating (TBC) to theoptical fiber prior to the additive manufacturing of the second part,wherein: the applying of the TBC comprises forming a protruding surfacefeature which protrudes away from the optical fiber, and the additivemanufacturing of the second part around the optical fiber comprisesforming a recessed surface feature, which corresponds in position to theprotruding surface feature and which extends into the second part toaccommodate the protruding surface feature.
 2. The method according toclaim 1, wherein the additive manufacturing of the first and secondparts comprises at least one of fused deposition modeling (FDM), fusedfilament fabrication (FFF), direct ink writing (DIW), stereo-lithography(SLA), digital light processing (DLP), powder bed and inkjet 3D printing(3DP), powder bed fusion (PBF), electron beam melting (EBM), selectivelaser melting (SLM), selective heat sintering (SHS), selective lasersintering (SLS), direct metal laser sintering (DMLS), laminated objectmanufacturing (LOM), directed energy deposition and electron beamfreeform fabrication (EBF³).
 3. The method according to claim 1, furthercomprising pre-loading the optical fiber coating with the TBC in thefiber channel.
 4. The method according to claim 1, wherein: theprotruding surface feature comprises a bump and the recessed surfacefeature comprises a dimple that is receptive of the bump or theprotruding surface feature comprises a hook shaped element and therecessed surface feature comprises a reverse hook shaped element thatmechanically interacts with the hook shaped element.
 5. The methodaccording to claim 1, wherein: the additive manufacturing of the firstpart comprises forming the trench to include first and second transversecomponents; the laying down of the optical fiber comprises laying downsections of the optical fiber with the TBC applied thereto in the firstand second transverse components; and the additively manufacturing ofthe second part comprises extending the first and second transversecomponents of the trench into first and second transverse components ofthe fiber channel.
 6. A method of additively manufacturing a component,the method comprising: additively manufacturing a first part such that afirst surface of the first part is formed to define a trench; layingdown an optical fiber in the trench; and additively manufacturing asecond part onto the first surface and around the optical fiber suchthat the first part and the second part redefine the trench as a fiberchannel in which the optical fiber is embedded, wherein the methodfurther comprises applying a coating to the optical fiber and forming aprotruding feature, which protrudes away from the optical fiber, and theadditive manufacturing of the second part around the optical fibercomprises forming a recessed feature, which corresponds in position tothe protruding feature and which extends into the second part toaccommodate the protruding feature.
 7. The method according to claim 6,wherein the additive manufacturing of the first and second partscomprises at least one of fused deposition modeling (FDM), fusedfilament fabrication (FFF), direct ink writing (DIW), stereo-lithography(SLA), digital light processing (DLP), powder bed and inkjet 3D printing(3DP), powder bed fusion (PBF), electron beam melting (EBM), selectivelaser melting (SLM), selective heat sintering (SHS), selective lasersintering (SLS), direct metal laser sintering (DMLS), laminated objectmanufacturing (LOM), directed energy deposition and electron beamfreeform fabrication (EBF³).
 8. The method according to claim 6, furthercomprising pre-loading optical fiber and the coating in the fiberchannel.
 9. The method according to claim 6, wherein: the additivemanufacturing of the first part comprises forming the trench to includefirst and second transverse components; and the laying down of theoptical fiber comprises laying down sections of the optical fiber withthe coating applied thereto in the first and second transversecomponents.